An experiment was made to test the potential for radicle emergence (RE), and predict the germination percentage of normal seedlings both at constant (25 °C) and fluctuating (20/30 °C, 16 h/8 h) temperatures for 23 commercially available Thiram treated and untreated aubergine (Solanum melongena L.) seed lots. Frequent counts of RE at 96, 104, 112, 120, 128 and 136 hours in two different temperature regimes (constant and alternating) consistently predicted final normal germination after 14 days. The R2 values at fluctuating temperatures (R2=0.69 and 0.88, p < 0.001) were generally higher than those at a constant (R2=0.60-0.63, p < 0.01) temperature. Among the 23 seed lots, nine were Thiram threated. The R2 relationship in both temperature regimes were reduced (for Thiram-threated seed lots ranging between R2=0.60-0.79 at 25°C and 20/30°C respectively, and for untreated lots ranging between R2=0.68-0.91 at 25 °C and 20/30°C, respectively). Cumulative germination was slightly higher in the lots kept at fluctuating temperatures than in those kept at a constant temperature. The results showed that the RE test (i.e. 104 h count) can be used to make quick and repeatable predictions of the percentage of normal seedlings in aubergine lots. Moreover it was also significantly related to mean germination time (MGT) values at constant (R2= 0.769, p < 0.001) and alternating temperatures (R2= 0.861, p < 0.001).

This work was carried out to estimate field and controlled room seedling emergence potential through seed vigour tests in cress (Lepidium sativum L.) seeds. Early radicle emergence percentages after 12 (RE12h), 24 (RE24h) and 36 (RE36h) hours of germination test, mean germination time, accelerated aging (45 °C, 100% RH, 24 h), electrical conductivity (EC) of soaking water (40 ml, 50 seeds, 20 °C), after 16 hours (EC16h) and 24 hours (EC24h), and EC16h and EC24h after accelerated ageing (AA, 45 °C, 100% RH, 24h) were tested as vigour tests in ten commercial seed lots of cress. Standard laboratory germination ranged between 88 and 93%. Seeds were sown on two occasions in field and controlled room conditions, and seedling emergence percentages were determined after 30 days in the soil and 14 days in the controlled room. Seedling emergence ranged between 67 and 85% and 59 and 83% in the first and second sowings in the field. These values were 75 and 92% in controlled room sowing. Vigour tests were correlated to seedling emergence potential at various significance levels but RE24h and EC16h showed the highest correlation coefficient values (p < 0.001) in all three sowing conditions as r = 0.879-0.988 in RE24h, and r = 0.902-0.962 in EC16h. Results indicated that early radicle emergence percentages after 24 hours (RE24h) and electrical conductivity value after 16 hours (EC16h) can be successfully used to estimate the seedling emergence potential of cress seeds in field and controlled room conditions. ********* In press - Online First. Article has been peer reviewed, accepted for publication and published online without pagination. It will receive pagination when the issue will be ready for publishing as a complete number (Volume 47, Issue 3, 2019). The article is searchable and citable by Digital Object Identifier (DOI). DOI link will become active after the article will be included in the complete issue. *********